The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 25, 2004
Filed:
Jun. 27, 2003
Michael J. Yancey, Puyallup, WA (US);
Tom J. Taylor, Seattle, WA (US);
Weyerhaeueer Company, Federal Way, WA (US);
Abstract
A method is described for determining a physical property of a log or similar wood member. A small amount of a liquid or solid is projected against the end of the log with sufficient energy to induce a stress wave. Water is a preferred liquid and an ice pellet is the preferred solid material. A water pulse of about 40 g or less shot from a distance of about 1.2 m with about 9-10,000 kPa pressure will induce a useful shock wave. Similarly an ice pellet weighing 5-10 g shot from the same distance at about 400-500 kPa has given excellent results. The travel time of the stress wave may be measured by an accelerometer in contact with the log. Alternatively, a laser Doppler vibrometer aimed at the log end can record the travel time. The use of the method obviates the need for a mechanical hammer striking the log as well as the requirement for the logs to be even ended at the test location.